Right now I'm using OpenSUSE 12.2 with KDE 4.9.4. If I upgrade that to KDE 4.10 in January, will it also bring in Qt 5 (or at least newer Qt packages)? Or are the Qt packages tied to the OS?
Just to add a little detail: OpenSUSE 12.2 is using libQt 4.8.1, while Tumbleweed and Factory (12.3) are using libQt 4.8.4. There will be no need to perform a major version upgrade to Qt5 in the foreseeable future. Equally, as harish provided; KDE4.10 does not require Qt5; so if you are running an installation of openSUSE Factory (which will receive Qt5 first) - you can hold back the packages by using Zypper's lock commands.